To Tell The Truth

Voice Card  -  Volume 16  -  Paul Card Number 12  -  Sun, Aug 5, 1990 11:25 PM

This is ONE OF 2 responses to Vol 15 Drury 2 ("These darn computers!")...

Will the REAL Master Controller please stand up?


John did a pretty good job answering most of the questions - good enough to fool most lay-people, I'm sure - but he botched the first one.

[Editor's note: "Botched?" I DID warn about reduced efficiency.]

To be precise, what he said was correct - but it was only part of the story. You *can* let your hard disk get pretty full without danger - but you *will* play a price for this fullness. Technically, the problem is known as "fragmentation", and the price of disk fragmentation is reduced performance. Let me explain:

As your disk begins to fill up, presumably with lots of files of various sizes, the computer has to search to find available space for new files. And as you delete old files, "holes" of available space open up at various locations on the disk. Soon you wind up with a disk that has *no* large blocks of contiguous free space, but lots of little pieces here and there.

The computer *is* smart enough to reuse these holes, even if they are not precisely the right size for your new files. However, jumping all around the disk looking for free space to store - or retrieve - files is time-consuming, and slows your computer down. And this problem with fragmentation increases more-or-less exponentially as you approach the capacity of your disk. A good rule-of-thumb: a disk more than three-quarters full will have this problem.

So, what to do? Your best bet is to buy - and use - a good defragmentation utility. These utilities reorganize your disk, collecting free space in one large block, and making individual files contiguous. SUM II is one such utility; fellow Archipelagans may be able to recommend other defraggers. A less expensive but more time-consuming alternative would be to back up your complete hard disk to floppies, reformat the hard disk, and restore the disk from floppies.

How do you tell if you're experiencing this problem? Subjectively, you probably won't notice the gradual deterioration of disk performance as fragmentation begins to set in over a period of weeks or months. Again, your best bet is to use a utility - SUM II and the others will report on current fragmentation before they fix it.

Note: I have been using DeFrag, a freeware CDEV to keep my disk fragmentation at bay. Recent reports suggest that this utility can cause subtle file corruptions. If any of you have DeFrag, YOU SHOULD STOP USING IT IMMEDIATELY!!!

End of lecture.

FlowFazer? I don't have the vaguest idea; I threw this out long ago. But it DID work on my machine. What did I claim it would do?